The possessive form is posse's.
Yes, the noun 'posse' is a standard collective noun for:a posse of policea posse of sheriffsa posse of turkeysa posse of posersIn recent times I've also heard the term a posse of paparazzi.
The award was created by George Washington and the current design of the Purple Heart was designed by John R. Sinnock of the Philadelphia Mint in 1931.
The noun 'posse' is a standard collective noun for:a posse of policea posse of sheriffsa posse of turkeysa posse of posersIn recent times I've also heard the term a posse of paparazzi.
The posse rode out to search for the escaped prisoner.
that depends on the posse
Amelie Posse died in 1957.
Amelie Posse was born in 1884.
Posse from Hell was created in 1961.
B.Brown Posse was created in 1992.
My Posse was created on 1987-01-01.
Shower Posse was created in 198#.